Prof Alec Jeffreys - DNA fingerprinting

Kat - Back in April I was at the Royal Society in London for the Genetics Society Spring meeting, Genomics for Health and Society. One of the most captivating talks of the day was from Professor Sir Alec Jeffreys, the inventor of DNA fingerprinting in the 1980s. It was initially used to resolve immigration disputes, proving whether people were really family members or not, and paternity disputes, then rapidly transformed crime detection. I asked him where he thought DNA fingerprinting technology is heading in the future.

Alec - Well, I think in terms of the technology we have at the moment, we're sort of trapped in a technology track using technology which is now round about 20 years old.  Now, we don't see that evolving a great deal certainly in crime detection. But I what I do see is broadening out into - if you think about DNA identification family relationships, your initial thoughts for catching the criminal, working out whether so and so was really the father of the child.  What's now emerging is much broader fields of DNA and genealogy and ancestry, and that sort of become pretty mature field but it's got a long way to go yet.

So, the question is, to what extent can we discover interesting things about your ancestry by scouring through your DNA sequences, comparing them with other individuals?  So, just as a hypothetical, let's suppose that we could take every single person in the United Kingdom, and sequence their entire genome.  You could take that information, and go a very long way towards establishing an incredibly detailed family tree of all the peoples of Britain.  A detailed genealogy and just imagine what you could do with that.  All these long lost third cousins you knew nothing about, all sorts of interesting connections with physical characteristics - you might have their facial features and all the rest of it.

Kat -   My mum would love this!

Alec -   So, I think the potential is there.  It does raise very thorny issues with genetic privacy and so on.  I mean, as soon as you start looking at the genome, yes, you'll come up with a lot of DNA variation which is informative in terms of ancestry, but not particularly important in terms of you as an individual.  But amongst that is going to be all sorts of potentially quite nasty surprises.  Mutations within your DNA that may well have health consequences.  So, tread carefully, interesting field, but there's a downside there potentially.

Kat -   And thinking more about crime and forensics, now that we can do whole genome analysis and we start to know what sort of genes encode for variations in characteristics, do you think maybe in the future, police will be able to reconstruct what a criminal will look like from just a sample of their DNA?

Alec -   Yeah, that is something that people, certainly, the police and scientists associated with forensics science, they've been interested actually with that over two decades and this notion of the DNA identikits.  So, can you go into DNA, what sort of physical characteristics can you predict from that?  And at least at the moment, it's fairly limited so we can do the sex of an individual.  Red hair, there's a good test for that, eye colour can be done, other things like facial features which is perhaps the most direct side of heritability that we all think about.  You know, little Jimmy's got his mum's eyes and his dad's nose.  Those are statements that do make sense.  We can see heritability of facial features, can you actually detect the DNA determinants that control the way we look.  Barely off the starting block and it may well be that it turns out to be so genetically complex.  You can never use it in a simple predictive forensic context.  But I would make the argument that the reason for doing that is not for police investigation.  It's just that most fascinating area of inquiry and that is, what makes us all unique.

Kat -   Why am I me?

Alec -   Yeah, why are you you and why do you look the way you do, and how does DNA influence that uniqueness as an individual?  So, I would see the future of forensic DNA very much as forensic DNA as part of a much bigger set of DNA inquiries which revolve around the individual - who I am as an individual, how the DNA contributes to that.

Kat -   And now that we have more and more DNA sequences and much more genomic information about more and more people, do you have any concerns about how this information might be used for example by the police or by the state, or by other individuals?

Alec -   Well, I mean a full genome sequence will by definition include all the information on all the genetic variants that are potentially damaging to you as an individual.  So, there are issues of genetic privacy there and the rights for either the National Health Service or government, whatever, to having information, highly personal private information of for instance disease liabilities.  But remember the information on your genome has implications for other people.  So, your genome isn't your genome.  Your genome is half of your mum and half of your dad's genome.  If you've got children, each of those will have been inherited half of it.  So, the genome is a shared thing and anything that you find out about your genome has immediate implications for close family relatives.  And again, that's all too often forgotten in this notion of personalised medicine that genomic information, helping you as an individual optimise your treatments or whatever which is fine.  But remember the level of the genome, it's just not you and all these relatives as well.

Kat -   When you first came up with the idea of genetic fingerprinting back in the '80s, did you have any idea how that field would grow and just how the field of genetics and genomics would explode?

Alec -   No way.  I mean, I saw - when we first came up with the notion of the DNA identification, sort of the day one, potentially, of utility in let's say in forensic investigations, but a technology of last resort.  So, if you were to tell me that today, there's well over 20 million convicted criminals now have their DNA profile database on national DNA databases for the total number of people worldwide that through criminal investigations, through paternities, through immigration case work, and so on have been - their lives have been directly affected by DNA tests.  Do we have a number?  I don't know.  Nobody is counting - 30, 40 million.  I have absolutely no idea, possibly more.  I mean, I would never have believed that.  So, it really has - I mean, the way it's spread and spread so rapidly is quite extraordinary.  I remember certainly in the early days, the driver for that spread was the community itself.  It wasn't government departments.  It wasn't the police.  It wasn't the lawyers insisting on this.  It was the families themselves trapped in disputes who suddenly saw DNA as the salvation.

Kat -   And then it's amazing to think that maybe the driver of the next genetic revolution could be people like my mum doing their family history.

Alec -   Oh, yes and that is quite likely.  I'm fairly sure that the genealogy, people doing family history is already a bit of a driver and this will become a much larger driver in the future.  I mean, I haven't had my genome done.  I'll be a bit leery about having it done so, I'd discover all the genetic nastinesses that are sort of lurking in my chromosomes, but I would love to have it done for genealogy.  One specific question which is sort of been attempted already but I don't think the answer is definitive is, I'm a Welsh Jeffreys, so is Judge Jeffreys, Baron George Jeffreys, the hanging judge.  So, maybe I'm a descendant of his.  Let's use DNA to find out.

Kat - That was Alec Jeffreys from the University of Leicester.